Abstract
Currently, Li-ion batteries are widely used to power mobile devices, owing to their high performance and huge flexibility. Societal issues lead the scientific research to improve the energy density, lifetime and enhance the safety of this storage system. In this way, twice thesis objectives are develop: high capacity negative electrode materials for the high energy density aspect, and innovative polymer electrolytes for more secure conditions, in collaboration with ADEME and Total.MSnSb negative electrode materials, with M a transition metal, have particularly caught our attention because of the remarkable electrochemical performance and unexpected TiSnSb cycling in temperature. In order to understand the transition metal influence, the study focused on the determination of the electrochemical behavior of NbSnSb and ZnSnSb2 electrode materials. The materials lithiation / delithiation reaction mechanisms have been depth highlighted by operando measurements (DRX, Spectroscopie Mössbauer and XAS). The electrode / electrolyte interface evolution, for different electrolytes and temperatures cycling, was investigated by several surface analyzes (XPS, Auger ...) to determine the solid electrolyte interphase (SEI) composition. Because the Li-ion batteries aging is caused by the formation of this passivation layer, we started to develop polymer electrolyte, which is a major challenge to improve the cyclability and safety of these devices. Cyclic polycarbonates are notably, and more specifically polymeric materials based on glycerol carbonate methacrylate. Electrochemical performance of gelled, crosslinked and all-solid polymer electrolytes were evaluated for Li-ion and Na-ion batteries.